JPH0245986B2 - INKUJETSUTOPURINTAHETSUDONOSEISAKUHOHO - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a method of manufacturing an inkjet printer head, and more particularly to a method of manufacturing an inkjet printer head by coating the inner surface of the nozzle of the head with a synthetic resin material.

(b) Background of the technology Inkjet printers have become rapidly popular due to their noiseless properties and the ability to use plain paper, but the on-demand system, which supplies the required amount of ink when it is needed, is especially effective at eliminating unnecessary ink. Since it is economically advantageous as it does not require collection equipment or high-voltage power supplies and requires few auxiliary equipment, its development and practical application are progressing in various fields.

(c) Prior Art and Problems The head of an inkjet printer, especially the above-mentioned on-demand type printer, includes intricate and minute ink channels and nozzles, and is not easy to manufacture. For example, the nozzle portion has a plurality of fine holes with an inner diameter of about 0.05 mm arranged at a constant pitch, and a complicated ink flow path for supplying ink is connected to the nozzle holes.

An example of a conventional method of manufacturing such an inkjet printer head is shown in the perspective view of FIG. In the figure, 1 is the head body, 2 is a plurality of nozzle holes 2
It is a nozzle plate having a. First, a pressure chamber 3, an individual ink channel 4, a common ink channel 5, and a connecting ink channel 6 are formed on the upper surface of a metal head body 1 made of stainless steel or the like by chemical etching or electrical discharge machining. Since the nozzle hole 2a at the leading edge of the ink flow path is a minute hole with an inner diameter of 0.1 mm or less, it is normally difficult to form using the above manufacturing method, so it is manufactured separately as the nozzle plate 2 by electroforming or the like. .

Thereafter, the head lid 7 is bonded to the head body 1 using a synthetic resin adhesive, and then the nozzle plate 2 is bonded to the position corresponding to the pressure chamber 3 so as to communicate with each other, thereby completing the process.

However, according to this manufacturing method, the ink flow path formed in the head body 1, especially the nozzle hole 2a,
Since the structure of the tip leading to the nozzle plate 2 is minute, when bonding the nozzle plate 2 to the pressure chamber 3, an excessive amount of synthetic resin adhesive may block part of the ink flow path or nozzle hole, causing clogging. Or, conversely, there may be a shortage and adjacent ink channels communicate with each other,
It is difficult to maintain high quality, the production yield is unstable, and it is not suitable for mass production. Furthermore, a similar problem occurs when the head cover 7 is bonded afterwards.

In addition, the nozzle holes 2a are minute, and it is difficult to manufacture the nozzle plate 2 itself, especially when the number of nozzle holes is large and there are multiple nozzle hole rows, and it is manufactured using metal electroforming or various other methods. However, the drawback is that the cost is high.

In order to eliminate the above-mentioned drawbacks, as conceptually shown in the partial cross-sectional view of FIG. After forming on main body 1,
A substance 9 such as a synthetic resin is attached to the edge of the opening passage 8 by a dropping method, a vacuum evaporation method, a sputtering method, etc., and the viscosity of the substance 9 is adjusted to form a predetermined inner diameter as shown in FIG. A method has been proposed in which the injection part 10, which becomes the nozzle hole 2a, is formed directly on the head body 1 (Japanese Patent Laid-Open No. 55-90377).

However, the injection part 1 of the nozzle hole 2a by the above-mentioned method
Maintaining the size and shape of the inner diameter of 0 to a predetermined accuracy depends on the viscous flow of the substance 9, which is extremely difficult to control and poses a major quality problem.

Furthermore, in JP-A No. 56-80476, a plurality of stainless steel wires having the same diameter as the nozzle hole are inserted in advance into a mold corresponding to the head body, and then after being filled with ceramic material and molded, A manufacturing method has been proposed in which the nozzle hole is integrally formed with the ink flow path by pulling out the wire. However, this manufacturing method has the problem that it is difficult to arrange a plurality of wires within the mold with high precision, and the work requires advanced technology.

(d) Object of the Invention The present invention has been made in view of the above-mentioned points, and it is an object of the present invention to provide a method for forming nozzle holes accurately (with high precision) and easily in manufacturing an inkjet printer head.

(e) Structure of the Invention The object of the invention described above is to provide a step in which a plurality of grooves having a cross section larger than the cross section of the nozzle hole are arranged in one main plane corresponding to the nozzle portion of the inkjet printer head main body; placing straight metal wires having a diameter equal to the inner diameter of the nozzle holes at predetermined positions in the plurality of grooves that will become the nozzle holes; and applying a curable synthetic resin liquid to the predetermined positions of each nozzle hole. a step of filling the metal wire so as to surround the metal wire, and a step of removing the metal wire after the hardening of the curable synthetic resin liquid and forming a nozzle hole communicating with the pressure chamber in the area where the metal wire was removed. This can be easily achieved by employing a method for manufacturing an inkjet printer head characterized by comprising:

(f) Embodiment of the Invention FIG. 3 is a conceptual perspective view for explaining an embodiment of the method for manufacturing a head based on the present invention.

It is conventional to form each ink flow path on one main plane of the head body 1 by the above-mentioned method, that is, etching method or electrical discharge machining method, etc. A hole forming groove 8 is formed. Now, assuming that the diameter of the predetermined nozzle hole 2a of the head is 0.05 mm, it is appropriate that the width and depth of the nozzle hole forming groove 8 are both about 0.1 mm.

Next, a straight metal wire 11 with a diameter of 0.05 mm, for example, a tungsten wire that has been scorched and restretched under a weight at high temperature in a hydrogen atmosphere, or a phosphor bronze wire that has been restretched in a cold state, is discharged to avoid burrs. Prepare a piece that has been cut to a specified size by processing. On the other hand, both side pieces 1 of a metal wire holding jig 12 having a U-shaped cross section as shown in the figure
2a with the same pitch as the nozzle hole 2a, and mount it on the base jig 20 side by side with the head body 1, and then form the nozzle hole forming groove 8 and the V groove Fix while matching the pitch of the grooves 13. Thereafter, the metal wire 11 is placed on the V-groove 13, and the length of the portion of the metal wire 11 existing in the nozzle hole forming groove 8 formed in the head main body 1 is a predetermined length L (the length of the nozzle hole forming groove 8 formed in the head body 1). 2a predetermined length + 0.5 mm).
At this time, adjust the V-groove 1 so that the center of the metal wire 11 exactly coincides with the center of the nozzle hole forming groove 8.
Form 3.

Thereafter, a synthetic resin liquid 14 adjusted to a viscosity of 10,000 to 20,000 C.PS is dropped into the nozzle hole forming groove 8, and the metal wires 11 are aligned with the position of the nozzle hole 2a. Fill it with. The head lid 7 is then adhered to the head body 1 with adhesive in the conventional manner.

After the synthetic resin liquid 14 is sufficiently cured by heat treatment, the metal wire 11 is pulled out to form the nozzle hole 2a accurately. In this case, if a mold release agent for synthetic resin is applied to the surface of the metal wire 11 in advance, the metal wire 11 can be pulled out more easily.

In addition, when it is necessary to finish the end surface 2b of the nozzle hole 2a smoothly, after curing the synthetic resin liquid 14 filled in the nozzle hole forming groove 8 as described above, cut off and remove the excess metal wire 11. The metal wire 11 remaining in the synthetic resin 14 is dissolved and removed using a chemical etching solution. In this case, the metal wire 11
It is convenient to use phosphor bronze as the material because it can be easily etched.

Further, depending on the structure of the inkjet printer head, the metal wire 11 remaining in the synthetic resin may be removed simply by mechanically pulling it out. For example, as conceptually shown in the plan view of FIG. 4a, in the case of an inkjet printer head for printing lines with a large pitch of nozzle holes 2a, the nozzle holes 2a, the pressure chambers 3, and the individual ink flow paths 4 are arranged at the same time. Can be formed in a straight line. Therefore, as shown in the figure, an escape groove 15 is previously formed on the head body 1 on an extension line of the pressure chamber 3 and the individual ink passage 4 so as to communicate with the individual ink passage 4. Y in Figure 4a
As shown in the cross-sectional view of FIG. 4b along line -Y,
A long metal wire 11 is placed on a predetermined position of the nozzle hole 2a, the pressure chamber 3, the individual ink flow path 4, and the relief groove 15, and the synthetic resin liquid 14 filled in the position of the nozzle hole 2a is cured. After that, the metal wire 11 is pulled out from the back side 1a of the head body, and the relief groove 15 is then closed with a synthetic resin material.

(g) Effects of the Invention As is clear from the above explanation, if the method for manufacturing an ink jet printer head according to the present invention is adopted, the connection between the ink flow passages of the head, which has a plurality of fine structures, and the nozzle holes 2a is improved. The formation of the part and the nozzle hole itself can be performed accurately and easily. Especially when it is necessary to finish the front surface of the nozzle hole smoothly, the nozzle hole is not clogged with polishing debris or abrasive, and a high-quality and highly reliable inkjet printer head can be obtained.

[Brief explanation of drawings]

FIG. 1 is a perspective view for explaining the conventional manufacturing method of an inkjet printer head, FIG. 2 is a cross-sectional view of the main part of the conventional head cited for explaining the present invention, and FIG. Figures 4a and 4b are conceptual perspective views for explaining one embodiment of the head manufacturing method based on the invention. FIG. 1 is a plan view and an enlarged sectional view for explaining an embodiment of the present invention in a head. 1 is the head body, 2 is the nozzle plate, 2a is the nozzle hole, 3 is the pressure chamber, 4 is the individual ink flow path, 5 is the common ink flow path, 6 is the connecting ink flow path, 7 is the head cover, 8 is the nozzle hole The forming grooves, 9 and 14 are synthetic resin, 10 is an injection part, 11 is a metal wire, and 15 is an escape groove.

Claims (1)

[Scope of Claims] 1. A plurality of ink channels 4 to 6 for introducing recording ink, a plurality of pressure chambers 3 for generating impact pressure on the ink, and the ink channel for ejecting the ink. A method of manufacturing an inkjet printer head having a plurality of nozzle holes 2a provided in communication with each other, the nozzle holes 2a being provided on one main plane corresponding to the nozzle portion of the inkjet printer head main body 1.
A step of arranging a plurality of grooves 8 having a cross section larger than the cross section of a, placing a straight metal wire 11 having a diameter equal to the inner diameter of the nozzle hole at a predetermined position in the plurality of grooves 8 that will become the nozzle hole. a step of filling each nozzle hole at a predetermined position with a curable synthetic resin liquid 14 so as to surround the metal wire 11; and a step of removing the metal wire after the curable synthetic resin liquid has hardened. and forming a nozzle hole 2a communicating with the pressure chamber 3 in the removed area.